Your Forest River Wildwood 170SSX FSX has a 79sqft frontal area and is 23ft long.
As you've discovered, your Honda Pilot can move it. Just not at highway speeds and up or down grades without excessive wear and tear and frayed nerves.
A large SUV with a V8 or Ecoboost will have the horse power and torque to move that frontal area at highway speeds and up/down grades more easily. Some good choices for that size trailer is Tahoe/Yukon, Suburban/Yukon XL, and Expedition/EL.
I've heard that the longer Suburban/Yukon XL and Exp EL tow better than the shorter SUV's. Expect anywhere from 6 to 10 mpg from any gasoline engine while towing and you won't be disappointed.
As this is a 3rd vehicle for you, mileage shouldn't be much of an issue as it isn't a daily driver. My "vacation only" Suburban towing a 7500lb 34ft trailer averages 9mpg.
Me'62, DW'67, DS'04, DD'07
'03 Chevy Suburban 2500LT 4WD Vortec8.1L 4L85-E 3.73 CurtClassV
'09 BulletPremier295BHS 33'4" 7200#Loaded 1100#Tongue Equal-i-zerHitch Tires:Kumho857
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